Serum levels of granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor in treated patients with chronic myelogenous leukemia in chronic phase

Abstract

BACKGROUND: Despite the fact that granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) are increasingly used in clinical practice, little is known of their endogenous production, especially in myeloproliferative disorders such as chronic myelogenous leukemia (CML). METHODS: In order to define serum levels of GM-CSF and G-CSF in subjects affected by CML, the sera of 17 patients with CML in chronic phase treated either with hydroxyurea or interferon-alpha were tested by specific enzyme immunoassays. Fifteen age- and sex-matched healthy volunteers were used as normal controls. RESULTS: Eight out of the 17 patients (44%) with CML showed detectable (> 3 pg/mL) serum levels of GM-CSF (range 3.9-55 pg/mL). Detectable levels (> 50 pg/mL) of G-CSF were observed in 9 of these patients (52%) (range 150-2,830 pg/mL). On the contrary, among the normal controls only one had detectable GM-CSF concentrations, and none had detectable G-CSF concentrations. The highest concentrations of both GM-CSF and G-CSF were seen in patients with the highest white blood cell counts, although a linear correlation between the levels of these growth factors and the number of circulating leukocytes was not demonstrated. CONCLUSIONS: Our data indicate that significant amounts of both endogenous GM-CSF and G-CSF are detectable in the serum of a substantial percentage of patients with CML in chronic phase. The pathophysiological meaning of this finding remains to be determined.